PDA

View Full Version : Chrome line vs. Chrome moly vs. Chrome Vanadium etc.


akjunkie
04-16-2012, 7:28 PM
What is the difference between the 3?

I'm looking for an 16in A3 Mid Length upper with A2 FSB, 1:9 twist, chrome lined barrel.
All I see is Chrome Moly. Doesnt anyone make it with a chrome lined barrel?

Something similar to this:

http://www.dsarms.com/DSA-ZM4-Forged-7075T6-A3-AR15-Upper-Receiver----ZM4CBUMIDNONFL/productinfo/ZM4CBUMIDNONFL/

Mail Clerk
04-16-2012, 7:47 PM
What is the difference between the 3?

I'm looking for an 16in A3 Mid Length upper with A2 FSB, 1:9 twist, chrome lined barrel.
All I see is Chrome Moly. Doesnt anyone make it with a chrome lined barrel?

Something similar to this:

http://www.dsarms.com/DSA-ZM4-Forged-7075T6-A3-AR15-Upper-Receiver----ZM4CBUMIDNONFL/productinfo/ZM4CBUMIDNONFL/

akjunkie,

In that basic M4 configuration there's allot of companies that make them with chrome lined barrels. Try Bravo Company or my favorite Riflegear. I have mine with just the chrome moly bore and it's fine to me although I much rather have a chrome bore too. I got mine from Model 1 Sales and it was fine. Just give the bore a good solvent cleaning before you shoot it! Mine had so much copper fouling it had to be solvent and scrubbed really good for almost a full day.

Good luck,

Mail Clerk:oji:

EvolutionGSR
04-16-2012, 7:53 PM
http://palmettostatearmory.com/index.php/ar-15-05/complete-uppers/psa-16-m4a1-upper.html

Only thing it doesn't have is the 1:9 twist. Its a 1:7

akjunkie
04-16-2012, 8:25 PM
How inferior is Chrome moly vs Chrome lined?

DSArms got the MID Length upper for $250 minus BCG and CH.
I wouldnt mind grabbing this. Just want to know how good is the chrome moly.

(I have a spare BCG and CH from last Xmas Group buy.)

ptgarcia
04-16-2012, 8:30 PM
You are comparing apples to oranges. Chromoly is the type of steel used to make the barrel. Chrome lining refers to a process the bore of the completed barrel undergoes.

akjunkie
04-16-2012, 8:40 PM
You are comparing apples to oranges. Chromoly is the type of steel used to make the barrel. Chrome lining refers to a process the bore of the completed barrel undergoes.

Ok, so a Chrome Moly barrel with NO lining inside the barrel is more prone to premature Rust & Wear?

MUKAK
04-16-2012, 9:17 PM
Ok, so a Chrome Moly barrel with NO lining inside the barrel is more prone to premature Rust & Wear?

yes..but not noticeable enuff to a civilian lol

milotrain
04-16-2012, 9:32 PM
1) Unlined barrels can be more accurate. Nearly all match rifles are not chrome lined. Chrome is used to inhibit rust and keep ware down so you can shoot high ammo counts without worrying about your barrel, they are not used to make a barrel more accurate. So "better" is an opinion.

2) I don't see any reason to get a 1:9 over a 1:7. A 1:7 will shoot anything a 1:9 will (that you can find) and it will shoot any of the heavier more accurate ammunition.

Meety Peety
04-16-2012, 9:48 PM
Chome lined is a coating on the bore of the barrel itself, not a build material. Chromoly is the build material itself. The difference between the two in realistic terms is miniscule, but it is said that an unlined barrel is slightly more accurate, while a lined barrel is more resistant to corrosion and wear. Like I said, the differences are miniscule because if you clean your bore correctly, you won't run into issues of corrosion. At the same time, unless you are building a highly precision gun and your abilities match the rifle, you won't notice a major difference in the accuracy. For the sake of information, the reason chrome lined barrels are said to be less accurate is that the lining itself is a coating, thus almost never consistently applied.

The main difference now comes down to wear and tear. There's no real way to measure this, because it greatly depends on cleaning habits, ammo choices and the shooting environment, but people do say that chrome lined barrels last a little longer. Most of the numbers I've seen people referencing are within 3,000 rounds of each other. Personally, I chose to go with a non-lined barrel because I was able to get a brand I wanted for the same price as a lesser brand's chrome lined. The accuracy observation also helped me in my choice, but realistically this rifle will greatly outshoot my potential.

For the record, I have seen people say that most chrome lined barrels are essentially a chromoly barrel with the added lining, thus the question really becomes chrome lined or not. I cannot confirm this, just something I've heard that makes a lot of sense. I think the reason places list non lined barrels as "chomoly" is to give off the impression that it isn't just "some lesser version" (it's not) which does lead the buyer to think there is something more there. I guess they don't want people to think its a choice between "fancy chrome lined" and "some whacky-*** pot metal".. which is not the case.

akjunkie
04-16-2012, 10:13 PM
Chome lined is a coating on the bore of the barrel itself, not a build material. Chromoly is the build material itself. The difference between the two in realistic terms is miniscule, but it is said that an unlined barrel is slightly more accurate, while a lined barrel is more resistant to corrosion and wear. Like I said, the differences are miniscule because if you clean your bore correctly, you won't run into issues of corrosion. At the same time, unless you are building a highly precision gun and your abilities match the rifle, you won't notice a major difference in the accuracy. For the sake of information, the reason chrome lined barrels are said to be less accurate is that the lining itself is a coating, thus almost never consistently applied.

The main difference now comes down to wear and tear. There's no real way to measure this, because it greatly depends on cleaning habits, ammo choices and the shooting environment, but people do say that chrome lined barrels last a little longer. Most of the numbers I've seen people referencing are within 3,000 rounds of each other. Personally, I chose to go with a non-lined barrel because I was able to get a brand I wanted for the same price as a lesser brand's chrome lined. The accuracy observation also helped me in my choice, but realistically this rifle will greatly outshoot my potential.

For the record, I have seen people say that most chrome lined barrels are essentially a chromoly barrel with the added lining, thus the question really becomes chrome lined or not. I cannot confirm this, just something I've heard that makes a lot of sense. I think the reason places list non lined barrels as "chomoly" is to give off the impression that it isn't just "some lesser version" (it's not) which does lead the buyer to think there is something more there. I guess they don't want people to think its a choice between "fancy chrome lined" and "some whacky-*** pot metal".. which is not the case.

Thanks!! This answered alot of questions for me.

Now i have something else to consider.
1) get a chrome lined barrel made out of "cheaper metal"
2) or get a NON chrome line barrel made out of "better/harder" material.

Options 2 makes more sense to me now.

akjunkie
04-16-2012, 10:18 PM
1) Unlined barrels can be more accurate. Nearly all match rifles are not chrome lined. Chrome is used to inhibit rust and keep ware down so you can shoot high ammo counts without worrying about your barrel, they are not used to make a barrel more accurate. So "better" is an opinion.

2) I don't see any reason to get a 1:9 over a 1:7. A 1:7 will shoot anything a 1:9 will (that you can find) and it will shoot any of the heavier more accurate ammunition.

I based my decision for a 1:9 barrel based on the info @ the Ammo Oracle plus all my Bushmaster uppers have 1:9 twist on them. However, I may try a 1:7 in the near future.

http://ammo.ar15.com/ammo/project/perf_whattwist.html

What twist rate do I want for my rifle?

Probably 1:9, but it depends on what kind of bullets you intend to shoot.

Special purpose rifles often have uncommon twist rates. For example, if you are building a varmint rifle and want to shoot the short 35 grain, 40 grain, and 50 grain bullets, a 1:12, or even 1:14 twist would be best. On the other hand, long range High Power shooters often select 1:8, 1:7.7, 1:7, or 1:6.5-twist barrels to stabilize the long 77, 80 and even 90 grain bullets used for 1,000 yard competition. Additionally, new testing of heavier rounds (68-77 grains) seems to show that they perform very well in simulated tissue and may be a better defensive choice than 55 grain or 62 grain rounds. The majority of shooters, though, typically shoot bullets of 50 to 69 grains in weight (note that the 62gr SS-109/M855 bullet is as long as a 71 grain lead core bullet) and should select 1:9 twist barrels. At typical .223 velocities, a 1:9 twist will stabilize bullet lengths equivalent to lead-core bullets of 40 to 73 grains in weight.

1:12 twist rifles cannot stabilize SS-109/M855 bullets and 1:7 twist rifles are slightly less accurate with lighter bullets and will often blow apart the thin jackets of lightweight varmint bullets. The 1:7 twist is used by the military to stabilize the super-long L-110/M856 tracer bullet out to 800 yards, but unless your plans include shooting a significant amount of M856, the 1:9 twist rate is better suited for general use.

There is, of course, an exception: if you want to use loads utilizing the heavier, 75-77 grain match bullets currently used by Spec-Ops troops and other selected shooters, you'll want a 1:7 twist barrel. Although military loadings using these bullets are expensive and hard to get, some persistent folks have managed to obtain a supply, and will need the proper barrel twist to use them. Anyone who foresees a need to shoot this ammo should consider a 1:7 twist barrel.

69powerwagon
04-16-2012, 10:24 PM
Chrome moly steel is somewhat of a misleading term as well. There are a lot of steels in the chrome moly spectrum. 4130,4140,4150,etc are frequently referred to as chrome moly steel. probably the chrome lined barrel is already chrome moly steel to start with. However. If you decide to go nonlined, chrome moly vanadium is a better option, however you would probably never notice the difference and just waste money for the vanadium. Here is a link to help explain a little better. http://www.m4carbine.net/showthread.php?t=37 I could explain more in depth if needed also.

akjunkie
04-16-2012, 10:41 PM
Chrome moly steel is somewhat of a misleading term as well. There are a lot of steels in the chrome moly spectrum. 4130,4140,4150,etc are frequently referred to as chrome moly steel. probably the chrome lined barrel is already chrome moly steel to start with. However. If you decide to go nonlined, chrome moly vanadium is a better option, however you would probably never notice the difference and just waste money for the vanadium. Here is a link to help explain a little better. http://www.m4carbine.net/showthread.php?t=37 I could explain more in depth if needed also.

Thanks fellas!! Calguns is a wealth of knowledge!!

milotrain
04-16-2012, 11:14 PM
The difference between the two in realistic terms is miniscule, but it is said that an unlined barrel is slightly more accurate, while a lined barrel is more resistant to corrosion and wear. Like I said, the differences are miniscule because if you clean your bore correctly, you won't run into issues of corrosion. At the same time, unless you are building a highly precision gun and your abilities match the rifle, you won't notice a major difference in the accuracy.
I disagree with this statement. A very good chrome lined barrel might hold it's own with a cheaper SS or CM barrel but the majority of chrome lined barrels are not of this quality.

I had a Sabre Defense chrome lined barrel and it is considered one of the better CMV barrels out there. It shot nicely, but not anywhere near as well as my cheap SS Wilson barrel (that I got used with 3700 rounds through it). With the SS Wilson I put 7 shots into a quarter at 100 yards. I could never have done that with the Sabre Defense barrel.

Again this is not to say that chrome lined barrels are bad, they are not. For specific purposes they are fantastic but to say that "the accuracy gain of going from a chrome lined barrel to a even basic quality SS barrel is minuscules" does not match with my experience.

jbush
04-17-2012, 1:15 PM
Thanks!! This answered alot of questions for me.

Now i have something else to consider.
1) get a chrome lined barrel made out of "cheaper metal"
2) or get a NON chrome line barrel made out of "better/harder" material.

Options 2 makes more sense to me now.

No, this is not the options as almost all barrels are 4140 or 4150 chrome moly. With the majority of ar barrels made of 4150. Chrome moly vanidium is another aditive to metal to help hardened it Anyway whatever it is called, the options are chrome lining or no chrome lining, the barrels are made of the same metal. They don't use cheaper metal and chrome line it. Look at the PSA barrels, they have chrome moly hammer forged barrels that are chrome lined. Hammer forged (a process for making barrels) barrels are very hard and they have them chrome lined.

As stated a chrome lined barrel is usual easier to clean, doesn't wear as fast, and resists corrsion better. A non chrome lined barrel can, but not necessarily, be more accurate, and if you clean it regularly, won't have a rust of corrision problem. I don't think the average person will shoot out a barrel, so the difference is up to you, as to chromelined or not.

I personally have a chrome lined barrel on my AR, but remember, almost all rifle barrels for hunting rifles etc. are non chrome lined 4140 or 4150 chrome moly and last most people a lifetime. The military uses chromlined barrels, but they fire full auto and are in very adverse conditions. Go to ar15.com and read the stickys under ar discussion and ar build it yourself, and a lot ofyour questions will be answered. There's a good one about barrel twist rates.

mif_slim
04-17-2012, 1:23 PM
I've shot a 36gr bullet out of a 1:8 and it tore the bullet apart at 100 yards. I was thinking how I missed at such a close range....until I saw the bullet was 36gr, I swap to 75gr and all is well with my soul. :D

jbush
04-17-2012, 1:58 PM
I disagree with this statement. A very good chrome lined barrel might hold it's own with a cheaper SS or CM barrel but the majority of chrome lined barrels are not of this quality.

I had a Sabre Defense chrome lined barrel and it is considered one of the better CMV barrels out there. It shot nicely, but not anywhere near as well as my cheap SS Wilson barrel (that I got used with 3700 rounds through it). With the SS Wilson I put 7 shots into a quarter at 100 yards. I could never have done that with the Sabre Defense barrel.

Again this is not to say that chrome lined barrels are bad, they are not. For specific purposes they are fantastic but to say that "the accuracy gain of going from a chrome lined barrel to a even basic quality SS barrel is minuscules" does not match with my experience.

Milotrain, this is comparing apples to oranges. I agree that most match or precision barrels are made of stainless steel and there accuracy is superior. But, they also wear out faster then chrome moly. What the OP was asking is the differences in Chrome moly, chrome moly vandium, and chrome lined. I don't think the barrel material is any less quality because the barrel is being chrome lined, however because the chrome cannot always be uniformily applied a non chrome barrel may be more accuate. Whether the OPs shooting ability is refined enough to notice the difference is something he must decide, but I believe the difference is so minor the average shooter would have a hard time telling the difference. There are a lot of different barrel makers and the quality of the barrel is obiviously dependent on the companies process for making barrels and their quality control. Comparing a SS barrel to a CMV barrel or a CL CMV barrel is not apples to apples IMO.

HK Dave
04-17-2012, 2:04 PM
Hehe I think this is being entirely over thought. :)

Whether it's chrome lined or not probably won't matter to a person asking the difference since it's highly unlikely they will go through the $3,000+ worth of ammo to actually wear down either barrel.

If that person does go through $3,000+ worth of ammo, the difference in price between barrels is inconsequential.

Get the chrome lined over the non chrome lined simply for the sake of easier cleaning. :D

skyungjae
04-17-2012, 2:08 PM
more expensive, therefore, better

:shifty:

milotrain
04-17-2012, 3:04 PM
but I believe the difference is so minor the average shooter would have a hard time telling the difference.

I agree with everything you said but this. I am if anything only slightly above the average shooter. I was not comparing them as an apples to apples comparison. Indeed I specifically pointed out that CMV-chrome lined barrels are better for some purposes. But they are inferior accuracy-wise. I know of a few cases where a chrome lined barrel was a match winning barrel but they are extreme exceptions. In almost every case a (SS or CM unlined) match barrel, even a button rifled, mass produced, $205 match barrel will noticeably out shoot a CMV-chrome lined barrel in the hands of anyone who has a rudimentary understanding of shooting accurately. If you don't know that you are supposed to focus on the front sight then maybe you won't notice a difference. If you do, or you have a scope, then at and past 100 yards you will almost surely notice a difference.

If you want a high ammo count barrel, a very environment resistant barrel, or a mag dump barrel then go get a CMV-chrome lined barrel. If you want an accurate barrel get a cheap SS or CM unlined match barrel.

One is not greater than the other, they are (as you say) different. You will notice their differences.

Richard Erichsen
04-17-2012, 3:36 PM
What is the difference between the 3?

I'm looking for an 16in A3 Mid Length upper with A2 FSB, 1:9 twist, chrome lined barrel.
All I see is Chrome Moly. Doesnt anyone make it with a chrome lined barrel?

Something similar to this:

http://www.dsarms.com/DSA-ZM4-Forged-7075T6-A3-AR15-Upper-Receiver----ZM4CBUMIDNONFL/productinfo/ZM4CBUMIDNONFL/

There are plenty of chrome-lined barrels, though for the average civilian user, it really won't make much difference (none of my old hunting rifles had chrome lined barrels). The unlined barrel, whether truly "plain" or Melonite QPQ (nitrocarburized) or plasma nitrided will tend to be slightly more accurate due to greater end to end bore consistency (chrome adds a slightly variable bore thickness which is costly and impractical to fully restore after plating). Barrel life for the unlined barrel will be in the order of 5000-6000 rounds before accuracy drops off significantly. A chrome lined barrel will be at least twice that number and as much as 25K rounds. The nitrocarburized barrels will last about as long as the chrome lined barrel without many of the disadvantages. Given ammunition prices, you're talking about a healthy ammunition budget to wear a barrel out and by the time you wear out the barrel other parts groups in your rifle are going to be up for overhaul as well.

The average shooter might only put a few hundred rounds through their rifle in a year, especially if you have several rifles in your arsenal to get range time on. As a practical matter you can only shoot one at a time and most range rules limit just how fast you can hurl lead without getting yourself in trouble. As a general rule, rapid fire and the heating of the barrel resulting from same is what eats barrels. Allowed to cool a bit between shots, a well made plain barrel can be very long lived indeed.

If you are authorized for a full auto weapon, or pump enough rounds through the rifle in a year to really worry about going through a barrel more than once per year, the chrome lined or nitrocarburized barrel might be of some benfit to you. On the other hand, if you can go through a pallet of ammo on a single rifle, the cost of a barrel is just a minor additive cost. You probably have all the necessary tools to rebarrel your upper or your favorite gunsmith on speed dial if you go through the kind of round counts we're talking about to eat a barrel. For most of us, the plain unlined barrel will last decades with only a modicum of cleaning after use.

Look carefully at your needs before you plunk down money for something that may or may not add much value. With the cost of ammo going up, I'd advise increasing the percentage of your firearms budget to ammo rather than fancy parts (boron-nickel treated bolt groups and the likes) that you'll probably never get the value out of. Probably not a bad idea in an election year, if we go by what happened in 2008, to load up on as much ammo as you can before the prices spike for awhile.

R

69powerwagon
04-17-2012, 3:41 PM
I agree with everything you said but this. I am if anything only slightly above the average shooter. I was not comparing them as an apples to apples comparison. Indeed I specifically pointed out that CMV barrels are better for some purposes. But they are inferior accuracy-wise. I know of a few cases where a chrome lined barrel was a match winning barrel but they are extreme exceptions. In almost every case a (SS or CM) match barrel, even a button rifled, mass produced, $205 match barrel will noticeably out shoot a CMV barrel in the hands of anyone who has a rudimentary understanding of shooting accurately. If you don't know that you are supposed to focus on the front sight then maybe you won't notice a difference. If you do, or you have a scope, then at and past 100 yards you will almost surely notice a difference.

If you want a high ammo count barrel, a very environment resistant barrel, or a mag dump barrel then go get a CMV barrel. If you want an accurate barrel get a cheap SS or CM match barrel.

One is not greater than the other, they are (as you say) different. You will notice their differences.


I'm a little confused as to what you are talking about. Are you referring to a chrome lined bore or a chrome molybdenum vanadium barrel as being inferior, cause adding vanadium does nothing to decrease accuracy. Seeding the steel with Vanadium makes for smaller crystal size, therefore increasing the toughness of steel. This is completely different than a chrome lined bore. Industry needs to drop the chromoly name and use the proper classification numbers because the current system only serves to confuse people and make good advertizing.

milotrain
04-17-2012, 4:25 PM
Sorry I'll go back and fix it. By CMV I mean a CMV barrel with a chrome line. I haven't ever found a CMV barrel without a chrome line, but that doesn't mean they don't exist. There are many SS and CM unlined match barrels and when I spoke about SS and CM barrels I was talking about unlined barrels.

702Shooter
04-17-2012, 4:26 PM
Thanks!! This answered alot of questions for me.

Now i have something else to consider.
1) get a chrome lined barrel made out of "cheaper metal"
2) or get a NON chrome line barrel made out of "better/harder" material.

Options 2 makes more sense to me now.


Option 3: http://criterionbarrels.com/Chromelining.html